STEREO Weekly Meeting Minutes for 2013-11-26 (Week 48) ANNOUNCEMENTS ------------- * None. INSTRUMENT and SPACECRAFT STATUS -------------------------------- * All subsystems on both spacecraft are nominal. DISCUSSION AND OPERATIONS CONSTRAINTS ------------------------------------- Week 47 (Nov 18-24) * On day 322 (Nov 18), during the DSS-65 support for Ahead, turbo decoder lock was lost intermittently beginning at 0712z through 1357z. This anomaly resulted in the loss of 616 frames of SSR data. See DR# M107585 more information. * On day 323 (Nov 19), during the DSS-55 support for Ahead, turbo decoder lock was lost intermittently beginning at 1357z through 1401z. The drop in signal level and receiver lock was caused by powering off the IMU following the momentum dump, which is a part of the reduced gyro operations. The engineer team is further analyzing the guidance and control performance to determine an adjustment to the momentum dump concept of operations. This anomaly resulted in the loss of 3458 frames of SSR data. The team has determined that they can't avoid the pointing glitch with the IMU is turned off, but they are looking into modifying the timing of the operation step to minimize the impact. * On day 326 (Nov 22), during the DSS-14 support for Ahead, turbo decoder lock was lost intermittently beginning at 1721z through 1725z due to weather. The SSR pointers for were repositioned prior to the outage and all data were recovered. See DR# G114427 more information. * On day 327 (Nov 23), during the DSS-54 support for Ahead, turbo decoder lock was lost briefly at 0802z. This anomaly resulted in the loss of one frame of SSR data. * On day 323 (Nov 19), the 62nd momentum dump was executed successfully on Ahead at 1330Z, which imparted a delta V of 0.088 m/sec. * On day 324 (Nov 20), the SSR science partitions on Ahead filled as follows: PLASTIC (Part 17) reached 95% full at 0405z for 3.6 hours. * On day 323 (Nov 19), during the DSS-25 support for Behind, turbo decoder lock was lost briefly at 2246z. This anomaly resulted in the loss of one frame of SSR data. * On day 326 (Nov 22), during the DSS-25 support for Behind, turbo decoder lock was lost briefly at 2352z. This anomaly resulted in the loss of one frame of SSR data. * On day 327 (Nov 23), during the DSS-26 support for Behind, turbo decoder lock was lost briefly at 2317z. This anomaly resulted in the loss of one frame of SSR data. * On day 328 (Nov 24), during the DSS-65 support for Behind, turbo decoder lock was lost briefly at 1026z. This anomaly resulted in the loss of one frame of SSR data. * On days 325-328 (Nov 21-24), the 13th-16th SECCHI 180 degree comet Ison rolls were executed successfully at 0600z each day. There was some discussion during the meeting that the SECCHI observations might have missed the comet because of a subfield mask error in the instrument. However, subsequent analysis after the meeting showed that the proper data were taken after all. Also, normal full-field images were taken during the rolls, and these also show the comet. * The average daily SSR playback volume during the week was 4.2 gigabits for Ahead, and 3.1 gigabits for Behind. Week 48 (Nov 25-Dec 1) * APL will be closed Thursday-Friday, Nov 28-29, for the Thanksgiving holiday. * Comet ISON reaches perihelion on Thursday, Nov 28. * The passes using station 15 with uncommitted data have been going well so far during the week. * 180 degree rolls of the Behind spacecraft to observe Comet ISON were carried out Monday-Tuesday, Nov 25-26, between 10-14 UT each day. * 290 degree rolls of the Behind spacecraft to observe Comet ISON will be carried out Saturday and Sunday, Nov 30-Dec 1, between 6-10 UT each day. * Ahead has 18 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Nov 25 (D63), Tuesday, Nov 26 (D63), Friday, Nov 29 (D63), Saturday, Nov 30 (D14), and Sunday, Dec 1 (D63, D14). The following tracks will be carried out at 160 kbps: Wednesday, Nov 27 (D54), and Friday, Nov 29 (D26). ESA New Norcia tracks are scheduled each day between Wednesday-Friday, Nov 27-29. * Behind has 17 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Nov 26 (D14), Thursday, Nov 28 (D14 at 720 kbps), and Friday, Nov 29 (D34, D14). The following passes will be carried out at 160 kbps: Monday, Nov 25 (D26), and Saturday, Nov 30 (D26). ESA Malargue passes are scheduled for Wednesday, Nov 27, and Thursday, Nov 28. Week 49 (Dec 2-8) * The first of the 30 degree rolls of the Ahead to observe Comet ISON are scheduled for Wednesday-Friday, Dec 4-6, between 0:01-4:00 UT each day. * 290 degree rolls of the Behind spacecraft to observe Comet ISON will be carried out Monday, Dec 2, 2-6 UT, Tuesday, Dec 3, 0:01-4 UT, Wednesday, Dec 4, 0:01-4 UT, Thursday, Dec 5, 0:01-4 UT, Friday, Dec 6, 0:01-4 UT, and Saturday, Dec 7, between 2-6 UT. * A station 24 pass on Tuesday, Dec 3, has been cancelled to support the MAVEN launch, and has been replaced with a station 15 pass. * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Dec 2 (D63), Wednesday, Dec 4 (D63), Friday, Dec 6 (D63), Saturday, Dec 7 (D63), and Sunday, Dec 8 (D63, D43 at 720 kbps). The station 15 pass on Thursday, Dec 5, will be performed with noncommitted data. An ESA New Norcia pass is scheduled for Tuesday, Dec 3. * Behind has 12 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Dec 2 (D43), Tuesday, Dec 3 (D43 at 720 kbps), Wednesday, Dec 4 (D43 at 720 kbps), and Thursday, Dec 5 (D43 at 720 kbps). The station 26 pass on Sunday, Dec 8, will be carried out at 160 kbps. Week 50 (Dec 9-15) * Simultaneous 30 degree rolls of Ahead, and 290 degree rolls of Behind, to observe Comet ISON, are scheduled for Monday-Wednesday, Dec 9-11, between 2-6 UT each day. * A transit of Mercury across the disk of the Sun will be observed by the Ahead spacecraft on Thursday, Dec 12, between approximately 2:00-7:20 UT. The complete period during which Mercury will be visible in either the COR1 or EUVI fields of view ranges from Wednesday, Dec 11, from approximately 11 UT, to Thursday, Dec 12, until approximately 19 UT, though visibility will depend on the coronal brightness behind Mercury. * The 28th SECCHI stepped calibration roll on Ahead is scheduled for Friday, Dec 13, starting at 04:05 UT. * Ahead has 8 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Dec 9 (D63,), Tuesday, Dec 10 (D63), Wednesday, Dec 11 (D14), Thursday, Dec 12 (D43), Saturday, Dec 14 (D63), and Sunday, Dec 15 (D63). * Behind has 11 passes during the week, and overall coverage is short 12 hours, mainly between Tuesday-Friday, Dec 10-13. A 70 meter pass is scheduled for Friday, Dec 13 (D14). The following passes will be carried out at 160 kbps, both using station 26: Wednesday, Dec 11, and Sunday, Dec 15. ESA New Norcia passes are scheduled for Thursday, Dec 12, and Friday, Dec 13. A station 15 pass was added on Saturday, Dec 14. Week 51 (Dec 16-22) * Simultaneous 30 degree rolls of the Ahead spacecraft, and 290 degree rolls of the Behind spacecraft, to observe Comet ISON are scheduled for Monday, Dec 16, 18-22 UT, Tuesday, Dec 17, 12-16 UT, and Wednesday, Dec 18, 2-6 UT. * The third battery discharge cycle on Behind is scheduled for Wednesday, Dec 18, starting at 13:30 UT. * The 63rd momentum dump on Ahead is scheduled for Thursday, Dec 19, with ignition at 13:30 UT. * The 58th momentum dump on Behind is scheduled for Thursday, Dec 19, with ignition at 15:00 UT. * Ahead has 13 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Dec 16 (D63), Tuesday, Dec 17 (D43 at 720 kbps), and Friday, Dec 20 (D63). * Behind has 12 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Tuesday, Dec 17 (D43), and Friday, Dec 20 (D43 at 720 kbps). The following passes will be carried out at 160 kbps, all using station 26: Wednesday, Dec 18, Friday, Dec 20, and Sunday, Dec 22. Week 52 (Dec 23-29) * Simultaneous 30 degree rolls of the Ahead spacecraft, and 315 degree rolls of the Behind spacecraft, to observe Comet ISON are scheduled for Monday, Dec 23, 18-22 UT, Tuesday, Dec 24, 12-16 UT, and Wednesday, Dec 25, 2-6 UT. * APL will closed for the Christmas holiday starting the afternoon of Tuesday, Dec 24, and on Christmas Day, Dec 25. * The 27th SECCHI stepped calibration roll is scheduled for Thursday, Dec 26, starting at 13:10 UT. This is the aphelion roll. * Ahead has 10 passes during the week, and overall coverage is nominal. 70 meter passes are scheduled for Monday, Dec 23 (D63), Tuesday, Dec 24 (D14), and Friday, Dec 27 (D63). The following passes will be carried out at 160 kbps: Monday, Dec 23 (D45), and Thursday, Dec 26 (D26). * Behind has 14 passes during the week, and overall coverage is nominal. A 70 meter pass is scheduled for Saturday, Dec 28 (D43 at 720 kbps). The following passes will be carried out at 160 kbps: Tuesday, Dec 24 (D26), Thursday, Dec 26 (D45), and Saturday, Dec 28 (D26). Week 01 (Dec 30-Jan 5) * Wednesday, January 1, is the New Year's Day holiday. * Spacecraft rolls to observe Comet ISON will be scheduled during the week, probably Monday-Wednesday, Dec 30-Jan 1. * Ahead has 8 passes during the week, and overall coverage is short 18.4 hours, mainly between Monday-Friday, Dec 30-Jan 3. 70 meter passes are scheduled for Tuesday, Dec 31 (D63), and Friday, Jan 3 (D63). The station 26 pass on Sunday, Jan 5, will be carried out at 160 kbps. * Behind has 8 passes during the week, and overall coverage is short 16.4 hours, mainly between Monday-Friday, Dec 30-Jan 3. 70 meter passes are scheduled for Saturday, Jan 4 (D63 at 720 kbps, D14). The following passes will be carried out at 160 kbps: Wednesday, Jan 1 (D25), and Sunday, Jan 5 (D25, D45). COORDINATED OBSERVATIONS ------------------------------------------------------------------------------- Scheduled activities for Week 48: M Nov 25 (329) Behind: 180 degree roll to observe Comet ISON, 10-14 UT T Nov 26 (330) Behind: 180 degree roll to observe Comet ISON, 10-14 UT W Nov 27 (331) T Nov 28 (332) Both: Perihelion passage of Comet ISON F Nov 29 (333) S Nov 30 (334) Behind: 290 degree roll to observe Comet ISON, 6-10 UT S Dec 01 (335) Behind: 290 degree roll to observe Comet ISON, 6-10 UT Notes: * Comet ISON in HI1 field-of-view on Ahead, Nov 21-28 * Comet ISON in HI1 field-of-view on Ahead unrolled, Dec 1-7 ------------------------------------------------------------------------------- Scheduled activities for Week 49: M Dec 02 (336) Behind: 290 degree roll to observe Comet ISON, 2-6 UT T Dec 03 (337) Behind: 290 degree roll to observe Comet ISON, 0-4 UT W Dec 04 (338) Ahead: 30 degree roll to observe Comet ISON, 0-4 UT Behind: 290 degree roll to observe Comet ISON, 0-4 UT T Dec 05 (339) Ahead: 30 degree roll to observe Comet ISON, 0-4 UT Behind: 290 degree roll to observe Comet ISON, 0-4 UT F Dec 06 (340) Ahead: 30 degree roll to observe Comet ISON, 0-4 UT Behind: 290 degree roll to observe Comet ISON, 0-4 UT S Dec 07 (341) Behind: 290 degree roll to observe Comet ISON, 2-6 UT S Dec 08 (342) Notes: * Comet ISON in HI1 field-of-view on Ahead unrolled, Dec 1-7 ------------------------------------------------------------------------------- Scheduled activities for Week 50: M Dec 09 (343) Ahead: 30 degree roll to observe Comet ISON, 2-6 UT Behind: 290 degree roll to observe Comet ISON, 2-6 UT T Dec 10 (344) Ahead: 30 degree roll to observe Comet ISON, 2-6 UT Behind: 290 degree roll to observe Comet ISON, 2-6 UT W Dec 11 (345) Ahead: 30 degree roll to observe Comet ISON, 2-6 UT Behind: 290 degree roll to observe Comet ISON, 2-6 UT T Dec 12 (346) Ahead: Mercury transit, 2:00-7:20 UT F Dec 13 (347) Ahead: SECCHI stepped calibration roll, 04:05 UT S Dec 14 (348) S Dec 15 (349) Notes: * Significant telemetry shortages are expected for the Behind spacecraft during the week. ------------------------------------------------------------------------------- Scheduled activities for Week 51: M Dec 16 (350) Ahead: 30 degree roll to observe Comet ISON, 18-22 UT Behind: 290 degree roll to observe Comet ISON, 18-22 UT T Dec 17 (351) Ahead: 30 degree roll to observe Comet ISON, 12-16 UT Behind: 290 degree roll to observe Comet ISON, 12-16 UT W Dec 18 (352) Ahead: 30 degree roll to observe Comet ISON, 2-6 UT Behind: 290 degree roll to observe Comet ISON, 2-6 UT Behind: Battery discharge cycle, 13:30 UT T Dec 19 (353) Momentum dumps: Ahead, 13 UT, Behind 15 UT F Dec 20 (354) S Dec 21 (355) S Dec 22 (356) ------------------------------------------------------------------------------- Scheduled activities for Week 52: M Dec 23 (357) Ahead: 30 degree roll to observe Comet ISON, 6-10 UT Behind: 315 degree roll to observe Comet ISON, 6-10 UT T Dec 24 (358) Ahead: 30 degree roll to observe Comet ISON, 2-6 UT Behind: 315 degree roll to observe Comet ISON, 2-6 UT W Dec 25 (359) Christmas Ahead: 30 degree roll to observe Comet ISON, 2-6 UT Behind: 315 degree roll to observe Comet ISON, 2-6 UT T Dec 26 (360) Behind: SECCHI stepped calibration roll, 13:10 UT F Dec 27 (361) S Dec 28 (362) S Dec 29 (363) ------------------------------------------------------------------------------- Scheduled activities for Week 01: M Dec 30 (364) T Dec 31 (365) W Jan 01 (001) New Year T Jan 02 (002) F Jan 03 (003) S Jan 04 (004) S Jan 05 (005) Notes: * Significant telemetry shortages are expected for both spacecraft during the week. ------------------------------------------------------------------------------- Upcoming events: 2013: * Dec 3-Jan 8 Ahead: 30 degree rolls 3 days/week for Comet ISON * Dec 20-Jan 8 Behind: 315 degree rolls 3 days/week for Comet ISON 2014: * Jan 20 Behind: End use of 480 kbps on 70 m DSN subnet * Apr 21 Behind: Resume use of 480 kbps on 70 m DSN subnet * Apr 29 Behind: Mercury transit * Sep 07-Nov 15 Behind: Passage of Comet Siding Spring through HI2-B * Oct 15 Behind: End use of 480 kbps on 70 m DSN subnet * Oct 17 Behind: Comet Siding Spring encounter with Mars 2015: * Jan 20 - Mar 28 (TBC) Behind: Spacecraft behind Sun * Mar DAWN - Ceres arrival * Mar 17 - Jul 14 (TBC) Ahead: Spacecraft behind Sun * Jul 2 Behind: Resume use of 480 kbps on 70 m DSN subnet * Aug 25 - Oct 19 (TBC) Behind: Spacecraft behind Sun * Sep 25 Behind: End use of 480 kbps on 70 m DSN subnet * Jul DAWN - End of nominal mission 2016: * Apr 3 Behind: Resume use of 480 kbps on 70 m DSN subnet * Jul Juno arrival at Jupiter 2017: * Jul 11 Ahead: Switch downlink rate to 160 kbps * Jul 22 Behind: Switch downlink rate to 160 kbps 2018: * Mar 5 Ahead: Mercury transit